Understanding male infertility | The secret of fertile sperm

To better understand the causes of male infertility, a team of Bay Area researchers is exploring the factors, both physiological and biochemical, that differentiate fertile sperm from infertile sperm. At the 58th Annual Biophysical Society Meeting, which takes place Feb. 15-19, 2014, in San Francisco, Calif., the team will present its work to identify and characterize proteins known as ion channels, which are crucial for sperm fertility and expressed within a sperm cell's plasma membrane. "Any knowledge gained in this area may help create much-needed diagnostic testing and treatments for male infertility, which is in essence an idiopathic disease, because at this time 80 percent of male infertility cases can't be diagnosed or treated," said Melissa Miller, a postdoctoral fellow who will present the team's findings at the meeting. Miller works in the labs of both of her co-authors, Polina Lishko of the University of California, Berkeley (UCB), and Yuriy Kirichok at the University of California, San Francisco (UCSF). To study ion channels, the researchers are recording the electrical activity of sperm ion channels under strictly controlled conditions. "Our labs have characterized three ion channels responsible for regulating calcium (CatSper), potassium (Slo1), and protons (Hv1) within sperm cells," Miller said. "So far, the most well-studied is the sperm cation channel CatSper, which is exclusively expressed within sperm cells and represents an ideal target for development of a unisex contraceptive; no other cell in the body is known to express this protein." Read more ... Article: 19th February 2014 www.sciencedaily.com

Fertility test to predict zero sperm viability for IVF

Scientists have developed a non-invasive test that can predict whether men with zero sperm counts are capable of fathering children through IVF. Current methods rely on surgery to find out if a man has viable sperm that can be retrieved for fertility treatment. The research, in Science Translational Medicine, suggests two biomarkers can identify who will benefit from surgery. A UK fertility expert said the test, which will take at least a year to bring to the clinic, was "encouraging". Male infertility is responsible for about half of cases of infertility. Men who produce no sperm can sometimes be helped to father a biological child through fertility treatment if they have normal sperm that can be extracted surgically. Others will never be able to father a child naturally and need to use donor sperm. With current technology, the only way to find out if a man has viable sperm is to carry out surgery to look for sperm in the testes. The new test, developed by scientists in Canada, has identified two biomarkers in sperm, which can be used to predict whether sperm retrieval will be successful. Dr Keith Jarvi of the Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital in Toronto, Canada, said the holy grail of his research was to find a way to help men avoid unnecessary testicular biopsies. He told BBC News: "The benefit of this is that we can predict without surgery whether or not a man has sperm or does not have sperm in the testicles. "You could avoid unnecessary surgery for a number of these men." He said work was under way to adapt the test for use in fertility clinics. "Optimistically, it would be a year away," he added. "Pessimistically, two years - we're moving along really quickly." Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield and chairman of the British Fertility Society, said the diagnosis of male infertility was tricky and it was hard to determine whether a man was producing sperm or not. The conventional method was to first examine semen under a microscope to see if sperm was there, he said. If no sperm was seen, the next step was to take tissue from a man's testicle and examine it with a microscope. "Quite understandably, many men would rather not undergo this procedure if they didn't have to," said Dr Pacey. "Therefore, having an accurate biochemical test which might help doctors advise men whether taking a piece of the testicle is worth doing or not, would be very useful. "It could help men make better decisions, avoid unnecessary surgical procedures and potentially help save money by not having to do surgical procedures that aren't needed. "The fact that two protein markers present in semen can be so well correlated with whether sperm are likely to be found is very encouraging indeed." Article: 21st November 2013 www.bbc.co.uk

Men with a poor sense of taste may have poor sperm or be infertile

A poor sense of taste in men may link to a problem with their sperm and fertility. Proteins that allow us to taste flavours play a crucial role in making men fertile, a study shows. American researchers found that two proteins, which allow the body to taste sweet and savoury flavours on the tongue, play a vital part in sperm development. The study, from the Monell Centre in Philadelphia, could suggest new ways to help male infertility or even spark the production of new male contraceptives. The surprising findings were made when mice were bred for taste related studies, without the two proteins known as taste receptors. They were found to be sterile, according to the study published in Proceedings of the National Academies of Sciences. Molecular Biologist Dr Bedrich Mosinger, said: 'This paper highlights a connection between the taste system and male reproduction. 'It is one more demonstration that components of the taste system also play important roles in other organ systems.' The taste receptors are more popularly known to help tongues detect sugars, salts and acids, which lead us to enjoy sweet, bitter, salty and sour tastes. While previous research has shown that taste receptors are located in different parts of the body, including the stomach and intestines, their function remains unclear. To try and work out their purpose, researchers examined the taste receptors that allow taste buds found on the tongue to detect sugars and amino acids that produce savoury and sweet tastes. LITTLE SENSE OF TASTE? COULD MEAN YOU LACK: Zinc. (RDA): 5.5-9.5mg for men Poor zinc intake can affect our sense of taste. In research carried out at the University of Ulster involving 387 people, those who had lower levels of zinc in their red blood cells were less able to detect salty tastes. How low zinc levels affect taste is unclear, but might be because zinc is required for the production of salivary enzymes and development and maintenance of tastebuds in general. Other signs of zinc deficiency can include more frequent infections, such as colds and flu, and delayed healing of wounds, probably because the mineral has a vital role to play in the functioning of the immune system and in the repair and renewal of cells. ZINC is important for sperm Zinc is an antioxidant mineral that is also important in protecting sperm against free radical attack. Semen is rich in zinc, with an estimate of each ejaculate containing as much as 5 mg - one third of the recommended daily nutrient intake. Thus a zinc deficiency would affect the protection of sperm. FOOD SOLUTION: Red meat - beef and lamb are among the best sources of zinc, so aim to eat one to two portions the size of an 8oz steak or equivalent a week. Other sources include nuts, especially cashews and peanuts, oysters, crab and dark chocolate. Article extracts: 2nd July 2013 www.dailymail.co.uk

Wi-fi from laptops could damage sperm say scientists

Scientists are questioning if using wi-fi on a laptop to searh the internet could harm a man's fertility, after lab work suggested ejaculated sperm were significantly damaged after only four hours of exposure.

The benchside tests showed sperm were less able to swim and had changes in the genetic code that they carry. Experts stress this does not mean the same would occur in a real-life setting and say men should not worry unduly. But they are recommending more studies.

The preliminary research, published in the journal Fertility and Sterility, looked at semen samples from 29 healthy donors. Each donor sample was separated out into two pots. One of these pots was then stored for four hours next to a laptop that was wirelessly connected to the internet. The other was stored under identical conditions, minus the laptop.

The scientists, from Argentina and the US, suspect that the effect seen is unrelated to the heat kicked out by a laptop, although heat can damage sperm.

The UK's Health Protection Agency has been closely monitoring the safety of wi-fi.
It says people using wi-fi, or those in the proximity of wi-fi equipment, are exposed to the radio signals it emits - and some of the transmitted energy in the signals is absorbed in their bodies. However, the signals are very low power.

The HPA says there is no consistent evidence to date that exposure to radio signals from wi-fi adversely affects the health of the general population.

UK fertility expert Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said: "The study is very well conducted, but we should be cautious about what it may infer about the fertility of men who regularly use laptops with wi-fi on their laps.

"Ejaculated sperm are particularly sensitive to many factors because outside the body they don't have the protection of the other cells, tissues and fluids of the body in which they are stored before ejaculation. Therefore, we cannot infer from this study that because a man might use a laptop with wi-fi on his lap for more than four hours then his sperm will necessarily be damaged and he will be less fertile.

"We need large epidemiological studies to determine this, and to my knowledge these have not yet been performed."
He said men should still be cautious about balancing a laptop on their thighs for hours on end.
"We know from other studies that the bottom of laptops can become incredibly hot and inadvertent testicular heating is a risk factor for poor sperm quality.

"There is a case report of a man who burnt his penis after using a laptop resting on his lap for a long time. Therefore, there are many reasons to try and use a laptop on a table where possible, and this may in itself ameliorate any theoretical concerns about wi-fi."

"The study is very well conducted, but we should be cautious about what it may infer about the fertility of men who regularly use laptops with wi-fi on their laps” UK fertility expert Dr Allan Pacey

Article: 30th November 2011 www.bbcnews.co.uk